1. Field of the Invention
The present invention relates to an inkjet printhead. More particularly, the present invention relates to an inkjet printhead with a plurality of ink channels through a substrate.
2. Description of Related Art
Inkjet printing technique has been broadly applied to printing equipments. According to the inkjet printing technique, droplets of ink is jetted onto a print medium to form ink dots on the print medium by a high pressure produced by actuators of a printhead (i.e. inkjet chip), accordingly an image or text is formed on the print medium by these ink dots. The most popular inkjet printing techniques include piezoelectric inkjet printing and thermal bubble inkjet printing. According to thermal bubble inkjet printing, ink is vaporized instantaneously by heaters (heating resistor) in the inkjet printhead for producing high-pressure bubbles, and the ink is then ejected through nozzles to form droplets of ink.
Specifically, in an existing thermal bubble inkjet printhead, a plurality of horizontal ink flow channels and ink chambers are usually formed with an ink chamber layer disposed on a substrate. The horizontal ink flow channels are formed in the ink chamber layer. Ink is vertically supplied to these horizontal ink flow channels via an elongated ink slot which is through the substrate and then enters the corresponding ink chambers through these horizontal ink flow channels. After that, the ink is vaporized by heaters disposed on the surface of the substrate and exposed by the ink chambers so that the ink is ejected through a plurality of nozzles on a nozzle plate disposed on the ink chambers to form droplets of ink.
It should be noted here that in an existing thermal bubble inkjet printhead, the elongated ink slot occupies a certain proportion of surface area of the substrate of the inkjet printhead, and relative long and horizontal ink flow channels are required for the ink to flow from the elongated ink slot into the heaters through the horizontal ink flow channels. The horizontal ink flow channels are disposed on the substrate, and are formed, for example, with the ink chamber layer. Thus, a lot of surface areas of the substrate of the inkjet printhead is taken by the elongated ink slot so that the number of heaters within the same surface area of the inkjet chip is limited, which in turn restricts the inkjet printhead from being developed towards high printing resolution, high printing speed, and low manufacturing cost.